Filter and process of filtering



Patented July 19, 1921.

1. H. HAEHRY.

FILTER AND PROCESS 0F FILTERING.

APPLICATION FILED .IAN- IO, 1920.

faz/g UNITED STATES PATENT orifice.

JOI-IN H. I-IAERRY, OF MILWAUKEE, .VISCONSIN.

FILTER AND PROCESS OF FILTERING'.

i Application filed. January 10, 1920. Serial No. 350,571.

To all w71 om t may concern.'

Be it known that I, JOHN I-I, I-IAERRY, a citizen of the United States,residing at Milwaukee, county of Milwaukee, and State of IVisconsin,have invented new and useful Improvements in Filters and Processes ofFiltering, of which the following is a specification.

This invention relates to filters and to the process of filtering.

One of the objects of this invention is to provide a filter in whichoxygen may readily be diffusedl throughout the filtering materialwithout the necessity of lemploying elaborate or complicated structuresforsecuring this result.

Y A further object is to provide a filter having the filtering materialarranged in vertical walls with the upper portion of the walls exposedto the air-and with the water traveling substantially horizontallythrough these vertical walls.

A further object is to provide a filter which is capable of being madein sizes for handling large quantities of water and which also handles alarge quantity of water in proportion to its size.

A further object is to provide a method of filtering whichsimplifies theconstruction of filters by employing a horizontal flow of water and avertical flow of air.

In the drawings- Figure 1 is a vertical sectional View of the filter.

Fig. 2 is a partial plan view of the filter.

The filter comprises acircular outer retaining wall 1 and a circularinner wall 2. Between these walls successive concentric vertical wallsof filtering material are positioned. The outer annular filtering wall 3consists of coke, the next wall 4 of fine sand, the third wall 5 ofcoarser sand, and the inner wall 6 of fine gravel. The walls 3 and 4L,which are of coke and fine sand, respectively, are thicker than thewalls 5 and 6. The sand not only performs its function of filtering butalso serves to retard, or hold the water in the chemically active cokelayer for a longer time than if the sand were absent. On account of thering formation and the positioning of the coke layer at the outside,such coke layer presents the largest crosssectional area of the severallayers.

An annular supply trough 7 fed by any suitable means, (notshown)furnishes water Specification of Letters Patent.

teria.

Patented July 19, 1921.

to the filter. A drain pipe 8, controlled by a valve 9, is provided forcleaning the trough 7. y From this annular supply trough,'vertical pipes10 extend downwardly to the bottom part of the structure and may restupon the bottom. These pipes may be of earthenware and are perforated onthe side next to the filtering rings at 12. These pipes may also befilled with pieces of unglazed earthenware, which absorb very easilydissolved and undissolved organic and inorganic substances. The watertherefore, passes from the supply trough under Zinc caps 13 anddownwardlythrough the pipes 10 into the filter. From the pipes the waterpasses radially inwardly through the successive layers of filteringmaterial and finally arrives at the central annular wall 2 which isprovided with a series of perfor-ations 14.i through whichthe waterfreely passes. This annular central member forms a small ternporaryreservoir for the filtered water which may be led therefrom through adelivery pipe 15 from the bottom of said chamber.

All of the walls and the bottom of the filter are form-ed of reinforcedconcrete and are set down a slight distance below the ground level 16.YAround the upper portion of the filter a packing of ashes 17 isprovided to form a heat insulating portion extending a considerabledistance outwardly so as to protect the filter from freezing. A shed 18mayy be Aprovided above the filter which may be supported upon rods 19set within the outer portion of the annular supply trough 7.

In the operation of this filter, the water passes downwardly through thetubes 10 and substantially horizontally through the filtering ring thegradient being indicated by the dotted line 19. The upper ends of thesefiltering layers are exposed to the air and a considerable'quantity ofoxygen is absorbed by these layers of filtering material, particularlythe coke layer 3. Chemical reactions take place in the coke layer, anduseful bacteria may live in such layer as it supplies the necessary air,but under the same conditions the harmful bacteria are destroyed. Cokehas the ability of absorbing large quantities of gases and harmful gasesare oxidized and rendered harmless by the bac- Disagreeable tastes andodors are removed in the coke layer. These actions @an not take place inthe usual filters for the reason that the horizontal layers of filteringmaterial are completely covered by the water and access of oxygenisprevented. yIf the water is a hard'water, containing soluble magnesiumand calcium salts, these salts are converted in the coke layer' intoinsoluble silicates, provided the water contains free silicio acid. Incase the water does not contain silicic acid, this deficiency may bereadily overcome by the addition of waterglass to the water in thetrough 7. Iron salts are oxidized to insoluble iron hydroxids. Iny casethevwater is objectionably acid, as for instance, water drawnfrom'forest or marsh ground containing numerous loam acids, limestone isplaced within the tubes l() to neutralize the acid.` In cases Where hardwater is required, the water can be hardened by putting gypsum into thesupply trough 7. i

This filter is admirably adapted to the handling of largerquantities ofwater as 1t may readily be made in large sizes by making the annularrings of a larger diameter following the same plan outlined above, or byforming an outer annular reservoir, for the filtered water, on theouterside of outer concrete wall and building successive filtering ringsaround such wall. As many of these additional concentric filtering unitsmay be used as are needed, each unit being complete in itself.

The process of filtering employed in this filter consists essentially inpassing the watery substantially horizontally through the layers offiltering material while allowing such layers to project upwardly intothe air above the water within such layers. By this arrangement, aquantity of oxygen is taken up by the filtering material such oxygenentering through the upper exposed portions thereof aswell as lthroughsome of the open-- ings 14S in the central reservoir 2. By employingthis process it is possible to use a gravity filter without an extensivesystem of pipes or other devices for bringing the oxygen to thefiltering material. i

Experimentsvhave shown that this kind of a filter filters 50%` morewater, in the same time, than a lcorresponding sand filter, and that thefiltered water is of a better quality. Experiments have also shown thatan ordinary sand filter has to be cleaned every montli,'while thisfilter need be cleaned only every twelve months.

` I claim :f

1. A filter comprising a plurality of verticall filtering walls, meansfor passing the water substantially horizontally therethrough, said'filtering walls being exposed to the air atonef end.

21 A filter comprising annular filtering walls, means yfor passing watersubstantially. horlzontal'ly therethrough, and means for'permittingoxygen to pass downwardly into the water through saidfiltering walls.

3. A filter comprising annular inner and outer vertical retaining walls,a series of concentric vertical filtering walls, positioned between saidfirst mentioned walls, an annular supply trough adjacent one of saidwalls, and means for causing water to pass through the action of gravitysubstantially radially through said filtering walls.

4L. A filter' comprising annular inner and outer vertical retainingwalls, a series of concentric vertical filtering walls, positionedbetween said'first lmentioned walls, and means for causing water to passvsubstantially radially through saidy filtering walls, the upper portionof said annular filtering walls being above the water level within saidwalls and freely exposed to the outer air.

5. A filter comprising annular inner and outer concentric verticalretaining walls, an annular trough arranged around the upper lportionof' the outer retaining wall, aV series of vertical walls composed offiltering material concentrically arranged, said filtering walls beingpositioned between said retaining walls and means for conducting thewater under the action `of gravity at aplurality of points from saidsupply trough to the outer portion of the outer annular filtering ring.

6. The process of filtering water, which process consists of passing thewater in a substantially*horizontal direction through filtering andoxygen absorbing material, and allowing oxygen to pass into saidmaterial, the line of flow of the oxygen being substantially at rightangles to that 'of the water. Y

7. The process of Vfiltering water which process consists of passingwater horizontally and substantially radially through filtering andoxygen absorbing material in such a manner that a material time isallowed for the passage Ythrough the oxygen absorbing material, andallowing oxygen to flow along'substantiallyV vertical pathsinto thewater by means of the oxygen absorbing material.Y Y

8. The process of filtering water which process consists ofV passingwater horizontally and substantially radially through coke in such amanner that a material time is allowed for the passage through the coke,and allowing oxygen to pass along substantially vertical paths intoV thewater by means of the coke.

In testimony whereof I affix my signature in the presence of twowitnesses. l

Y JOHN H. HAERRY. vWitnesses WALTER A. KUEBLER, A.R. VVooLFoLx, Jr.

